This study is aimed at examining the relationships between floatation parameters, assessed by fie... more This study is aimed at examining the relationships between floatation parameters, assessed by field tests and the stroking characteristics of breaststroke swimmers. The floatation parameters were evaluated for 23 males and 23 females by the hydrostatic lift test, the sinking force acting at the ankle test and the maximal glide length after a push-off from the pool wall test. The swimmers performed two trials at submaximal and sprint pace, and then, from the data given by a PC-video velocity system, the duration and velocity of their propulsive, recovery and glide phases were analyzed. In the female group and at slow pace, glide duration is correlated with hydrostatic lift (r = .62) and with maximal glide length (r = .44); mean glide velocity is correlated with hydrostatic lift (r = .73). In the male group and at slow pace, the sinking force was correlated with the glide phase (r = –0.66) and with the mean glide velocity (r = –0.78). At sprint velocity, the hydrostatic lift is correl...
This study proposes a new method to evaluate arm-leg coordination in flat breaststroke. Five arm ... more This study proposes a new method to evaluate arm-leg coordination in flat breaststroke. Five arm and leg stroke phases were defined with a velocity-video system. Five time gaps quantified the time between arm and leg actions during three paces of a race (200 m, 100 m and 50 m) in 16 top level swimmers. Based on these time gaps, effective glide, effective propulsion, effective leg insweep and effective recovery were used to identify the different stroke phases of the body. A faster pace corresponded to increased stroke rate, decreased stroke length, increased propulsive phases, shorter glide phases, and a shorter T1 time gap, which measured the effective body glide. The top level swimmers showed short time gaps (T2, T3, T4, measuring the timing of arm-leg recoveries), which reflected the continuity in arm and leg actions. The measurement of these time gaps thus provides a pertinent evaluation of swimmers' skill in adapting their arm-leg coordination to biomechanical constraints.
Le paraplégique en fauteuil roulant soumet son territoire sus-lésionnel à de nombreuses contraint... more Le paraplégique en fauteuil roulant soumet son territoire sus-lésionnel à de nombreuses contraintes. Au sein de ce territoire, le rachis cervical est l'un des complexes prédisposés à être le lieu de sollicitations mécaniques intenses. Le handicap et la position assise ont été au ...
The purpose of this study was to analyse the effect of swimmer specialty on energy cost and motor... more The purpose of this study was to analyse the effect of swimmer specialty on energy cost and motor organization. The stroking parameters (velocity, stroke rate, stroke length, stroke index) and the index of coordination (IdC) of 6 elite sprinters were compared with those of 6 elite long-distance swimmers during an incremental swimming exercise test (6x300 m separated by 30 s of passive recovery) that progressively increased the energy cost. Energy cost ( C), with its aerobic ( Caero) and anaerobic ( Canaero) components, was determined by measuring oxygen uptake (VO2) and blood lactate ([La]). Motor organization was assessed by analysis of video recordings from aerial and underwater side-view cameras. The results showed that throughout the test, both groups increased C, Canaero, stroke rate and IdC and decreased Caero and stroke length (all P<0.05). On the mean of the 300-m sets, sprinters had higher values for C (14.8 VS. 12.9 J x kg (-1).m (-1)), Canaero (33.8 VS. 23.4%), [La] (5...
The aim of this study was to compare the arm-leg coordination in flat breaststroke among four gro... more The aim of this study was to compare the arm-leg coordination in flat breaststroke among four groups of swimmers (elite males, elite females and non-elite males, non-elite females) of two different competitive levels. Using a velocity-video system, both forward acceleration and deceleration phases of the hip were first identified. Based on these phases, four temporal gaps indicated the time duration between arm and leg actions throughout three race paces (200, 100, and 50 m). For both groups, a velocity increase was combined with an increase of stroke rate, a decrease of stroke length, and an increase of the propulsive phases and a decrease of the glide phases. However, when the relative duration of one stroke cycle was considered, the elite swimmers had significant shorter time of the glide phase than lower competitive level swimmers (18.80 % vs. 31.04 % for females and 11.89 % vs. 19.60 % for males) combined with a longer stroke length (respectively 2.05 m vs. 1.73 m and 2.03 m vs...
This study is aimed at examining the relationships between floatation parameters, assessed by fie... more This study is aimed at examining the relationships between floatation parameters, assessed by field tests and the stroking characteristics of breaststroke swimmers. The floatation parameters were evaluated for 23 males and 23 females by the hydrostatic lift test, the sinking force acting at the ankle test and the maximal glide length after a push-off from the pool wall test. The swimmers performed two trials at submaximal and sprint pace, and then, from the data given by a PC-video velocity system, the duration and velocity of their propulsive, recovery and glide phases were analyzed. In the female group and at slow pace, glide duration is correlated with hydrostatic lift (r = .62) and with maximal glide length (r = .44); mean glide velocity is correlated with hydrostatic lift (r = .73). In the male group and at slow pace, the sinking force was correlated with the glide phase (r = -0.66) and with the mean glide velocity (r = -0.78). At sprint velocity, the hydrostatic lift is correl...
In this study, we compared the reliability of short-term resting heart rate (HR) variability (HRV... more In this study, we compared the reliability of short-term resting heart rate (HR) variability (HRV) and postexercise parasympathetic reactivation (i.e., HR recovery (HRR) and HRV) indices following either submaximal or supramaximal exercise. On 4 different occasions, beat-to-beat HR was recorded in 15 healthy males (21.5 ± 1.4 yr) during 5 min of seated rest, followed by submaximal (Sub) and supramaximal (Supra) exercise bouts; both exercise bouts were followed by 5 min of seated recovery. Reliability of all HR-derived indices was assessed by the typical error of measurement expressed as a coefficient of variation (CV,%). CV for HRV indices ranged from 4 to 17%, 7 to 27% and 41 to 82% for time domain, spectral and ratio indices, respectively. The CV for HRR ranged from 15 to 32%. Spectral CVs for HRV were lower at rest compared with Supra (e.g., natural logarithm of the high frequency range (LnHF); 12.6 vs. 26.2%; P=0.02). HRR reliability was not different between Sub and Supra (25 v...
This study is aimed at examining the relationships between floatation parameters, assessed by fie... more This study is aimed at examining the relationships between floatation parameters, assessed by field tests and the stroking characteristics of breaststroke swimmers. The floatation parameters were evaluated for 23 males and 23 females by the hydrostatic lift test, the sinking force acting at the ankle test and the maximal glide length after a push-off from the pool wall test. The swimmers performed two trials at submaximal and sprint pace, and then, from the data given by a PC-video velocity system, the duration and velocity of their propulsive, recovery and glide phases were analyzed. In the female group and at slow pace, glide duration is correlated with hydrostatic lift (r = .62) and with maximal glide length (r = .44); mean glide velocity is correlated with hydrostatic lift (r = .73). In the male group and at slow pace, the sinking force was correlated with the glide phase (r = –0.66) and with the mean glide velocity (r = –0.78). At sprint velocity, the hydrostatic lift is correl...
This study proposes a new method to evaluate arm-leg coordination in flat breaststroke. Five arm ... more This study proposes a new method to evaluate arm-leg coordination in flat breaststroke. Five arm and leg stroke phases were defined with a velocity-video system. Five time gaps quantified the time between arm and leg actions during three paces of a race (200 m, 100 m and 50 m) in 16 top level swimmers. Based on these time gaps, effective glide, effective propulsion, effective leg insweep and effective recovery were used to identify the different stroke phases of the body. A faster pace corresponded to increased stroke rate, decreased stroke length, increased propulsive phases, shorter glide phases, and a shorter T1 time gap, which measured the effective body glide. The top level swimmers showed short time gaps (T2, T3, T4, measuring the timing of arm-leg recoveries), which reflected the continuity in arm and leg actions. The measurement of these time gaps thus provides a pertinent evaluation of swimmers&#39; skill in adapting their arm-leg coordination to biomechanical constraints.
Le paraplégique en fauteuil roulant soumet son territoire sus-lésionnel à de nombreuses contraint... more Le paraplégique en fauteuil roulant soumet son territoire sus-lésionnel à de nombreuses contraintes. Au sein de ce territoire, le rachis cervical est l'un des complexes prédisposés à être le lieu de sollicitations mécaniques intenses. Le handicap et la position assise ont été au ...
The purpose of this study was to analyse the effect of swimmer specialty on energy cost and motor... more The purpose of this study was to analyse the effect of swimmer specialty on energy cost and motor organization. The stroking parameters (velocity, stroke rate, stroke length, stroke index) and the index of coordination (IdC) of 6 elite sprinters were compared with those of 6 elite long-distance swimmers during an incremental swimming exercise test (6x300 m separated by 30 s of passive recovery) that progressively increased the energy cost. Energy cost ( C), with its aerobic ( Caero) and anaerobic ( Canaero) components, was determined by measuring oxygen uptake (VO2) and blood lactate ([La]). Motor organization was assessed by analysis of video recordings from aerial and underwater side-view cameras. The results showed that throughout the test, both groups increased C, Canaero, stroke rate and IdC and decreased Caero and stroke length (all P<0.05). On the mean of the 300-m sets, sprinters had higher values for C (14.8 VS. 12.9 J x kg (-1).m (-1)), Canaero (33.8 VS. 23.4%), [La] (5...
The aim of this study was to compare the arm-leg coordination in flat breaststroke among four gro... more The aim of this study was to compare the arm-leg coordination in flat breaststroke among four groups of swimmers (elite males, elite females and non-elite males, non-elite females) of two different competitive levels. Using a velocity-video system, both forward acceleration and deceleration phases of the hip were first identified. Based on these phases, four temporal gaps indicated the time duration between arm and leg actions throughout three race paces (200, 100, and 50 m). For both groups, a velocity increase was combined with an increase of stroke rate, a decrease of stroke length, and an increase of the propulsive phases and a decrease of the glide phases. However, when the relative duration of one stroke cycle was considered, the elite swimmers had significant shorter time of the glide phase than lower competitive level swimmers (18.80 % vs. 31.04 % for females and 11.89 % vs. 19.60 % for males) combined with a longer stroke length (respectively 2.05 m vs. 1.73 m and 2.03 m vs...
This study is aimed at examining the relationships between floatation parameters, assessed by fie... more This study is aimed at examining the relationships between floatation parameters, assessed by field tests and the stroking characteristics of breaststroke swimmers. The floatation parameters were evaluated for 23 males and 23 females by the hydrostatic lift test, the sinking force acting at the ankle test and the maximal glide length after a push-off from the pool wall test. The swimmers performed two trials at submaximal and sprint pace, and then, from the data given by a PC-video velocity system, the duration and velocity of their propulsive, recovery and glide phases were analyzed. In the female group and at slow pace, glide duration is correlated with hydrostatic lift (r = .62) and with maximal glide length (r = .44); mean glide velocity is correlated with hydrostatic lift (r = .73). In the male group and at slow pace, the sinking force was correlated with the glide phase (r = -0.66) and with the mean glide velocity (r = -0.78). At sprint velocity, the hydrostatic lift is correl...
In this study, we compared the reliability of short-term resting heart rate (HR) variability (HRV... more In this study, we compared the reliability of short-term resting heart rate (HR) variability (HRV) and postexercise parasympathetic reactivation (i.e., HR recovery (HRR) and HRV) indices following either submaximal or supramaximal exercise. On 4 different occasions, beat-to-beat HR was recorded in 15 healthy males (21.5 ± 1.4 yr) during 5 min of seated rest, followed by submaximal (Sub) and supramaximal (Supra) exercise bouts; both exercise bouts were followed by 5 min of seated recovery. Reliability of all HR-derived indices was assessed by the typical error of measurement expressed as a coefficient of variation (CV,%). CV for HRV indices ranged from 4 to 17%, 7 to 27% and 41 to 82% for time domain, spectral and ratio indices, respectively. The CV for HRR ranged from 15 to 32%. Spectral CVs for HRV were lower at rest compared with Supra (e.g., natural logarithm of the high frequency range (LnHF); 12.6 vs. 26.2%; P=0.02). HRR reliability was not different between Sub and Supra (25 v...
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